In the next presidential debate, Trump took some time at the podium to address the size of his hands and his "something else."

Rubio told Tapper that he didn't like how the joke reflected on his own character.

"It embarrassed my family. It's not who I am," Rubio said. "What I didn't realize was it isn't who I am and if you're not being who you are it doesn't come across well."

Rubio said the comment came at a moment in the election where it was increasingly evident that none of the attacks or criticisms levied at Trump were working.

"This guy is out there every day mocking people, saying horrible things about people, but if you respond to him somehow you are hitting below the belt?" he said. "And he can do that because of whatever reason, he can do that. But I couldn't do that.

"It isn't who I am, it isn't what I do, and by doing that I ended up hurting myself, not him."